This invention relates generally to the manufacture of coil zippers and, specifically, this invention relates to a method of making coil zippers flame retardant and water repellent.
Over the last few years, various government agencies have been requiring the treatment of certain fabric articles to make them flame retardant. These requirements have been especially stringent in manufacturing clothing and, in particular, clothing for children. Yet, the requirement for making certain articles flame retardant is not limited only to clothing but covers a wide variety of fabric materials. Furthermore, there are many fabric articles which are treated by their manufacturers to be flame retardant notwithstanding the fact that there might not be any particular requirement to do so. Thus, there are a wide variety of articles which are made flame retardant, either because of laws or regulations, or completely voluntarily. These articles include not only clothing, and in particular, children's clothing, but they also include camping equipment such as tents and sleeping bags, draperies and curtains, and the like. The treatment of the fabric used to make these articles is usually fairly straight-forward.
But, many of these articles are produced from fabric and then have attached to them a variety of fasteners such as zippers.
Most people think of a zipper as being a metal fastener, but they are unaware that the latest development in zippers is the so-called coil zipper which is completely fabricated of a plastic material, usually a polyester. Furthermore, the zipper is combined with a fabric tape which, in turn, is attached to the garment or other article by stitching or some other suitable means. The fabric of the tape is also usually a polyester.
The reasons for making a fabric item water repellent and self-evident. Raincoats, jackets, tents, sleeping bags, etc. must be water-repellent as well as flame-retardant.
It is not complete satisfactory to manufacture a garment or tent, for instance, using a flame retardant and water repellent fabric only to include a zipper which may not be flame retardant and water repellent or which may be mounted on a fabric tape which is not flame retardant and water repellent. In fact, a panel in which an untreated coil zipper is sewn into a flame retardant canvas, may not be able to meet the flammability requirements of MVSS-302. This occurs because of the thermoplastic nature of a coil zipper and the inherent flammability in its construction.
Yet, the normal methods for impregnating a fabric with a flame retardant material and a water repellent material are not completely satisfactory for rendering a coil zipper flame retardant and water repellent. Furthermore, the hygroscopicity of most flame retardants and flammability of common water repellents complicates the matter of obtaining such a dual treatment. It is for these reasons that flame retardant and water repellent coil zippers have heretofore not been made.